I got a Lamy with the ink cartridge already installed and it worked wonderfully every time I picked it up. When I ran out of ink I got these replacement cartridges and inserted one and now for some reason, it takes foreverrrr to get it going every time I want to write. Like the ink just will not come out. Not sure if its my fault or they are faulty cartridges :/ wish I could recommend but I just can't. Due to this issue, my once favorite pen is gathering dust.